Dental prosthetics that are permanently attached (fixed) to the teeth are called fixed prosthetics. Crowns, bridges (fixed dentures), onlays, inlays, and veneers are also referred to as indirect restorations. Professionals in prosthodontics have trained in this area from academic institutions. With fixed prosthodontics, a single tooth or multiple teeth can be restored over areas where teeth are missing. A common oral health issue is trauma-induced tooth hypersensitivity following preparation of the tooth. Dental hypersensitivity is caused by a sudden onset of sharp pain on contact with exposed dentin, usually in response to heat, evaporation, pressure, or cold and is not attributed to any other dental problem or condition." Despite a lack of literature on the subject, post-cementation sensitivity has not been definitively studied. When dentinal tubules are separated during the preparation of teeth, a certain degree of pulpal trauma will result. An important decision is whether to carry out elective endodontic treatment for the tooth's vital abutments or proceed with the pulp preservation procedure.

Aim: to indicate the importance of adequate selection of all on four-fixed implant supported hybrid mandibular prosthesis material to reduce bone stresses. Materials and methods: one three-dimensional simplified geometric model, for bone and fixed prosthesis, was created by using engineering CAD/CAM software. On the other hand, implant system manufacturer data gave sufficient geometrical data to model it exactly. The modelled part was transferred to ANSYS for assembly, meshing, and analysis. Three overlying materials were tested; Acrylic, Polycarbonate, and Zirconia above the cobalt chromium bar. The lowest area of the cortical bone was set to be fixed in place as boundary condition. While unilaterally load of 250N was applied vertically on central fossa of first and second molars as two loading cases. Results: changing overlying material resulted in, cortical bone and implant complex receiving Von Mises stress in sequence with material rigidity. The more rigid the overlying material the less bone stresses with first molar loading, while, opposite trend (sequence) appeared with second molar loading. On the other hand, bar, coping, screws, mucosa, and spongy bone deformations and stresses decreased with increasing overlying material rigidity. Where, all the model components showed stresses and deformations within the physiological limits. Conclusions: More rigid overlying material is recommended to reduce stresses on bar, coping, screws, mucosa, and spongy bone. Overlying material selection for cortical bone and implant complex is extremely tricky. That it showed same behaviour as other soft tissues with applying load close to the bar (short cantilever arm), then inverted behaviour with shifting the applied load away from first to second molar (increasing cantilever arm).

The maintenance of stringent oral hygiene practices is imperative during orthodontic treatment in order to prevent plaque from accumulating over braces and other orthodontic appliances, leading to gingivitis inflammation and periodontal disease. Consequently, an orthodontist is responsible for providing advice to patients about oral hygiene to maintain periodontal health and for monitoring plaque control measures. In spite of their orthodontist's recommendation, most orthodontic patients do not follow their recommended instructions on how to maintain a satisfactory level of plaque control. We conducted our systematic review of literature in English. During the initial re-examination phase, there were no filters applied to ensure all studies were available for subsequent screening. Filters like human studies were added later, with English language studies being the only ones added. We found nine articles related to orthodontic treatment, and their relation to dental care, during our literature review. It is essential to maintain good oral hygiene during orthodontic treatment to reduce iatrogenic demineralization and caries. When a patient's DMFS score is high, prophylaxis programs are necessary during orthodontic treatment.

Background: Stain color of CAD/CAM prosthetic materials is important for the long-term of these materials without affecting daily beverage consumption habits. Aims: To assess the influence of aging with Coca-Cola drinks on the color of the CAD/CAM materials used for inlay and veneer restoration over different time intervals. Methods: 48 specimens were fabricated from Vitablocs Mark II and zirconia CAD/CAM ceramic materials. Each group comprised 24 specimens with eight samples for every background (white [W], black [B], and gray). Baseline readings were taken by a spectrophotometer before staining (Baseline T0). After Coca-Cola staining and aging, the color measurement was repeated after 15 and 30 days (T1 and T2), while T3 was the difference between T2-T0. The data were analyzed with descriptive statistics, one-way ANOVA, and post hoc tests. Results: The ΔE00 color parameters of Mark II and zirconia materials were higher against the W background than other backgrounds. However, the zirconia materials recorded higher values than Mark II for the same parameters (L, a, and b) against the gray background during 15 and 30 days of immersion in Coca-Cola. Translucency parameters (TP) exhibited significant differences between ceramic types and immersion periods, with the TP values of zirconia being slightly higher than those of Mark II. The ΔE00 values for the three-time intervals were within clinically acceptable ranges. The ΔE00 values of both ceramic types at T3 were within 1.38–1.53 and 3.11–3.62 and lacked significant differences. Conclusions: Coca-Cola staining was obvious after 15 and 30 days of immersion and had a marked effect on the TP and ΔE00 of the tested CAD/CAM materials. Increasing the staining time resulted in a reduction in TP values at all time intervals. Zirconia samples had higher ΔE00 values than Mark II materials at different time periods. All of the colors of the tested materials had changed from B1 to different light colors in accordance with the Vita classical shade guide.